# std::map<Key,T,Compare,Allocator>::insert_range

From cppreference.com
< cpp‎ | container‎ | map

template< container-compatible-range<value_type> R > void insert_range( R&& rg ); |  | (since C++23)

Inserts a copy of each element in the range rg if and only if there is no element with key equivalent to the key of that element in *this.

Each iterator in the range rg is dereferenced exactly once. The behavior is undefined if rg overlaps with the container.

No iterators or references are invalidated.

### Parameters

rg | - | a container compatible range, that is, an `input_range` whose elements are convertible to `T`
Type requirements
- `value_type` must be EmplaceConstructible into `map` from *ranges::begin(rg). Otherwise, the behavior is undefined.

### Return value

(none)

### Complexity

N·log(a.size() + N), where `N` is ranges::distance(rg).

### Notes

Feature-test macro | Value | Std | Feature
--- | --- | --- | ---
`__cpp_lib_containers_ranges` | `202202L` | (C++23) | Ranges-aware construction and insertion

### Example

Run this code

    #include <iostream>
    #include <map>
    #include <utility>

    void println(auto, auto const& container)
    {
        for (const auto& [key, value] : container)
            std::cout << '{' << key << ',' << value << '}' << ' ';
        std::cout << '\n';
    }

    int main()
    {
        auto container = std::map{std::pair{1, 11}, {3, 33}, {2, 22}, {4, 44}};
        const auto rg = {std::pair{-1, -11}, {3, -33}, {-2, -22}};
    #ifdef __cpp_lib_containers_ranges
        container.insert_range(rg);
    #else
        container.insert(rg.begin(), rg.end());
    #endif
        println("{}", container);
    }

Output:

    {-2,-22} {-1,-11} {1,11} {2,22} {3,33} {4,44}

### See also

insert | inserts elements or nodes(since C++17) (public member function)

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